1. Field of the Invention
This invention relates to cardiopulmonary support apparatus and more particularly to a novel closed emergency bypass system having simplicity of operation and economy in use providing inherent advantages as compared with current therapies.
2. Brief Description of the Prior Art
In the past, it has been the conventional practice to employ a plurality of various extracorporeal blood circulation components in blood oxygenation and delivery systems in connection with the care of patients with disease states such as: coronary artery disease, acute atrio-ventricular valve insufficiency, ruptured septum, left ventricular aneurysm. However, prior systems are limited in application and are not used for such diseases as: myocardial infarction, cardiogenic shock, congestive heart failure, septic shock, pulmonary embolus, pulmonary edema, shock lung, chronic obstructive pulmonary disease, adult respiratory distress syndrome, smoke inhalation, drowning and drug overdose.
It is routine practice to employ a conventional membrane-type oxygenator as a major component in a multicomponent system as shown in FIG. 3 in the manner described as follows:
Venous blood is accessed through cannulae placed in the superior and inferior vena cavae. This blood is siphoned from the patient through the "patient venous supply" line and into a flexible "venous reservoir" bag. A totally occlusive roller-type "venous pump" propels blood from the venous reservoir bag through a heat exchanger, an oxygenator, and into a flexible "arterial reservoir" bag. The arterial reservoir bag is connected to the venous reservoir bag by a "recirculation line." Another totally occlusive roller-type pump, the "arterial pump," pumps blood from the arterial reservoir bag back to the patient. A third occlusive roller-type pump, the "coronary perfusion pump," propels blood from the arterial reservoir into the root of the aorta to effect cardioplegia. Two more totally occlusive roller-type pumps, the "suction pumps," are used to aspirate blood shed into the pericardial sac or into the pleural spaces, or to evacuate blood from the left ventricular cavity. The final component of the extant circuitry for running the membrane oxygenator is a "water temperature control unit" which pumps water through the heat exchanger.
Problems and difficulties are encountered when employing the conventional oxygenator described above which stem largely from overall complexity and quantity of the various components used in the circuit. For example, at least three blood reservoirs are employed as well as four pumps and attendant tubing and interconnections. Obviously, complicated supervisory requirements and operator expertise are needed and set-up time is substantial. All of these difficulties adversely effect manufacturing cost, patient price, and the number of potential accidental patient hazards.
Therefore, a long standing need has existed to provide a novel means or apparatus for reducing circuit and component complexity whereby inherent advantages are gained as compared with prior and existing cardiopulmonary support systems.